Integrating polarization conversion system

US6411437B1 · kind B1 · utility

Assignee

• Corning Precision Lens, Inc. · US

Inventors

• Bruce Cannon · Portland, US
• Arlie R. Conner · Tualatin, US

Key dates

• Filing date: Jun 28, 2000
• Grant date: Jun 25, 2002
• Expiry date: Jun 28, 2020

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B27/283
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A polarization conversion system provides generally uniform polarized illumination light while maximizing illumination brightness by utilizing all illumination light, particularly the typically brightest illumination light available in a central region. In one implementation, the polarization conversion system includes a pair of lens arrays that successively receive light from an illumination source. A planar array of polarization beamsplitters is positioned adjacent the latter lens array. Each polarization beamsplitter includes a pair of elongated right-angle prisms having their respective inclined faces positioned against each other and their lengths extending vertically across multiple lenslets of the latter lens array. The polarization beamsplitter array includes coplanar top and bottom array segments, the inclined faces of the prisms of the polarization beamsplitters of the top array segment being oriented at substantially one angle (e.g., +45°) and the inclined faces of the prisms of the polarization beamsplitters of the bottom array segment being oriented at substantially a reversed angle (e.g., −45°). The top and bottom polarization beamsplitter array segments…